Subtract 30/32 from 21/40
21/40 - 30/32 is -33/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 32 is 160
Next, find the equivalent fraction of both fractional numbers with denominator 160 - For the 1st fraction, since 40 × 4 = 160,
21/40 = 21 × 4/40 × 4 = 84/160 - Likewise, for the 2nd fraction, since 32 × 5 = 160,
30/32 = 30 × 5/32 × 5 = 150/160 - Subtract the two like fractions:
84/160 - 150/160 = 84 - 150/160 = -66/160 - After reducing the fraction, the answer is -33/80
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